The key to the smart industry lies in the collection of data and information. Sensors are the nerve endings of the smart industry. They are used to collect data and provide basic data support for the construction of the smart industry. At the same time, with the rapid development of the Internet of Things, Industry 4.0, and intelligent manufacturing, application requirements are getting higher and higher. Smart sensors that collect the most initial data are rapidly upgrading and iterating, driving the intelligent transformation of industrial Internet terminals. “Industrial Sensor 4.0” or the era of industrial sensors is booming. It ranges from industrial process sensing and factory automation, from microcontrollers and wired or wireless connections to cloud servers.
Smart sensors used for industrial
In industrial automation, sensors play a vital role in making production intelligent and automated. These allow people to monitor, analyze, and process various changes that occur on the industrial manufacturing site, such as changes in temperature, motion, pressure, altitude, external, and security.
Almost every process or environmental condition has a suitable sensor type. The smart sensor integrates signal conditioning, MEMS technology, and firmware, so as to meet the easy-to-use and low-cost perception needs of industrial design engineers, and greatly reduce the development burden of design engineers.
Types of industrial sensors
The following are the major types of industrial sensors commonly used in automation:
- Temperature / Humidity Sensors
- Pressure Sensors
- Level Sensors
- Flow Sensors
- Proximity Sensors
- Position Sensors
- Vibration Sensors
- Gas Sensors
- Smoke sensors
- Optical Sensors
In addition, industrial sensors may employ different sensing technologies, such as infrared, ultrasonic, radar, and MEMS technologies.
1. Temperature / Humidity sensors
In industrial production, temperature and humidity are the most frequently measured physical parameters. A temperature sensor is a device that collects temperature information from the environment and converts it into a specific value. Among them, digital temperature sensors and temperature and humidity sensors are the most commonly used in industrial automation.
The digital temperature sensor sampling card has a ten-digit dual-channel successive approximation A/D converter and a standard RS-232 or 485 communication interface. The product adopts a filtering method that combines recursive average digital software filtering and hardware circuit filtering to minimize external interference to sampling, with high full-scale accuracy, strong stability, good consistency, and fast response.
The temperature and humidity sensor is an integration of a temperature sensor and a humidity sensor. The temperature and humidity probes are used as temperature measurement components to collect temperature and humidity signals, and after circuit processing, they are converted into current signals or voltage signals that are linearly related to temperature and humidity. It can also be directly passed through the main control chip. Perform interface output such as 485 or 232.
Application of temperature sensors: Temperature sensors are widely used in various industries, such as medical industry, industry, food industry, hydropower station, petrochemical industry, metallurgy industry, printing, and dyeing pharmaceutical industry and other industries have applications.
2. Pressure sensors
A pressure sensor is a device that detects pressure and converts it into an electrical signal which can be measured, transmitted, or processed by a control system. The pressure sensor is usually composed of a pressure sensitive element and a signal processing unit. Pressure sensors are integral to the operational integrity of a fluid filled pipeline. They are capable of identifying pipeline leaks, obstruction or the malfunction of an element in the system. They are used by a monitoring system to provide an alert to operational maintenance staff.
Application of pressure sensors: Pressure sensors are among the most widely used sensors in industrial applications. It is widely used in many industries such as water conservancy and hydropower, railway transportation, intelligent buildings, automated production, aerospace, military, petrochemicals, oil wells, power, shipbuilding, machine tools, and pipelines.
3. Level sensors
A level sensor is a device used to measure and monitor the level of liquids or bulk solids. It converts level information into an electrical signal output. Level sensors are used to determine the liquid level in open or closed systems. Liquid level measurement can be divided into continuous measurement and point level measurement. The continuous level sensor provides real-time level measurement across the entire measurement range. The point level sensor is used to determine whether the liquid level is high or low.
Application of level sensors: Although level sensors are massively employed in the industrial sector, they can also be found in various products we use daily, such as water heaters and washing machines. Water heaters, for instance, use level sensors to detect and refill the water in the tank to the preset maximum level. Toilets also use level sensors to ensure that a certain water level is maintained in the tank, preventing overflow.
4. Flow sensors
A flow sensor is an instrument used to measure the flow rate of a fluid (including liquids, gases, or steam) in a pipe or channel. It converts the fluid flow information into an electrical signal that can be measured and processed.
Flow sensors can be categorized into volumetric flow sensors and mass flow sensors. These are based on measurement principles. While volumetric flow sensors measure the volume of fluid that passes through the system at a certain interval, mass flow sensors measure the mass of the fluid.
Applications of flow sensors: Flow sensors are among the most commonly used industrial sensors. These sensors are employed in the water treatment industry, in oil and gas and chemical pipeline processes, in the manufacturing of food and beverages and pharmaceuticals, in HVAC systems and in the automation of process systems.
5. Proximity sensors
A proximity sensor can detect an object’s nearness. It can register if an object is present or near it without contact, and convert into an electrical signal. Because of the nature of contactless measurement, no damage is incurred to the object and, combined with the absence of a spark or noise, proximity sensors are known to have a long lifetime. When compared to other measurement techniques, proximity sensors are not affected, or really affected at all, by the presence of dirt, water, or oil on the object being measured.
Examples of proximity sensors can include inductive, capacitive, photoelectric, and ultra-sonic sensors. Inductive proximity sensors are predominantly for the detection of metal objects, while the latter three are for the detection of a wider range of materials such as plastics, and glass, as well as liquids and all other non-metallic objects. Each proximity sensor type is known to have a specific range or distance which can be measured, or effectively detected, at a distance of a few to tens of millimeters.
Applications of proximity sensors: Proximity sensors are widely used in aviation, aerospace technology, and industrial production. In daily life, such as hotels, restaurants, garages, automatic doors, automatic hot air blowers have applications. In terms of security and anti-theft, such important places as data files, accounting, finance, museums, and vaults are usually equipped with anti-theft devices composed of various proximity switches. In the measurement technology, the measurement of length and position; in the control technology, such as the measurement and control of displacement, velocity, and acceleration, there are also a large number of proximity switches for users.
6. Position sensors
A position sensor is a device that detects the spatial position or displacement of an object and converts it into an electrical signal. It can use linear sensors to detect linear motion or rotary sensors to detect angular motion. The output is a continuous numerical signal.
Applications of position sensors: Position sensors are widely used in industrial automation production lines, automotive navigation systems, parking sensors, aircraft navigation and positioning, smart home systems, and other applications.
7. Vibration sensors
A vibration sensor is basically a device that turns mechanical vibrations into electrical signals. It’s able to collect data on how fast and far something is vibrating, as well as how much it’s moving back and forth. This information can be really useful for things like figuring out how healthy a machine is, or if it’s starting to break down. The sensor can do things like analyze the average vibration level, look at the highest points of vibration, and even break down the vibrations into different frequencies to help diagnose problems.
Based on their operating principles, vibration sensors can be classified into piezoelectric, capacitive, magnetoelectric, inductive, eddy current, MEMS, and resistive types. Utilizing principles such as the piezoelectric effect, electromagnetic induction, capacitance changes, and micro-electro-mechanical systems (MEMS) technology, they convert mechanical vibrations into quantifiable and analyzable electrical signals, providing data support for equipment condition monitoring and fault diagnosis.
Applications of vibration sensors: Vibration sensors are among the most important industrial sensors. They’re really good at keeping an eye on equipment that rotates, like motors and pumps. But that’s not all – they’re also used in mining, machinery manufacturing, and even in the aerospace industry.
8. Gas sensors
A gas sensor is a device that converts the composition and concentration of a gas into an electrical signal. It uses various methods, such as adsorption, chemical reaction, and optical detection, to convert the target substance into an electrical signal, which is then input into a data system to enable the detection and analysis of compound concentrations.
Gas sensors play a crucial role in many industrial processes, where they’re used to keep an eye on various gases like oxygen, carbon dioxide, carbon monoxide, methane, and hydrogen sulfide, among others. These sensors can be set up to monitor just one type of gas or multiple gases at the same time, depending on what’s needed for the specific application. This flexibility is really important, because different industries have different requirements when it comes to gas detection.
Applications of gas sensors: As one of the most common types of industrial sensors, gas sensors are really common in lots of industries, like manufacturing, coal mining, and chemical plants. They’re also used in airplanes and other areas. Plus, they’re super important in hospitals and healthcare. For instance, carbon dioxide sensors help us keep an eye on the air quality inside buildings, making sure we’re breathing in good air.
9. Smoke sensors
The smoke sensor can detect smoke particles generated during a fire and send out an alarm signal in time. The smoke sensor is an indispensable sensor in a flammable and explosive industrial production environment. When smoke sensors are integrated with industrial IoT solutions, even the slightest gas leak or minor fire can be reported to the relevant team, thereby avoiding major disasters.
Application of smoke sensors: Widely used in HVAC, construction site monitoring, and industrial units with the high possibility of fire and gas leakage.
10. Optical sensors
The optical sensor is based on the optical principle for measurement. It has many advantages, such as non-contact and non-destructive measurement, almost no interference and remote control. They convert changes in light intensity, reflection, transmission, or interruption into electrical signals that can be processed by monitoring and control systems. In industrial applications, it is mainly used to detect whether the target object appears, or to perform various industrial automation motion detection.
Application of optical sensors: Widely used in industrial automation places such as telecommunications, elevators, construction, healthcare, and security systems.
An infrared sensor is a device that uses infrared to process data. Infrared is also called infrared light. It has properties such as reflection, refraction, scattering, interference, and absorption. Any substance, as long as it has a certain temperature (above absolute zero), can radiate infrared rays.
The infrared sensor is not in direct contact with the measured object during measurement, so there is no friction, and it has the advantages of high sensitivity and fast response. The infrared sensor can control the operation of the drive device. Infrared sensors are often used for non-contact temperature measurement, gas composition analysis, and non-destructive testing.
Application of infrared sensors: Infrared sensors are widely used in the fields of medicine, military, space technology, and environmental engineering. Infrared sensors integrated with industrial IoT solutions are also used in other industries.
MEMS (Micro-Electro-Mechanical Systems) sensors are miniature sensors manufactured using microelectronics and micromachining technologies. Compared with traditional sensors, it has a small size, low power consumption, high reliability, and is suitable for mass production. The feature size on the order of micrometers allows it to perform functions that cannot be achieved by some traditional mechanical sensors.
Application of MEMS sensors: As a key device for obtaining information, MEMS sensors have played a huge role in the miniaturization of various sensing devices. They have been used in space satellites, launch vehicles, aerospace equipment, aircraft, various vehicles, and special It has been widely used in the fields of medicine and consumer electronics.
Conclusion
As the entrance to the information collection, sensors are the “heart” of the Internet of Things, smart industries, and smart devices. The realization and development of the Industrial Internet are inseparable from the wide application of sensors and technological innovation. However, on the other hand, the Industrial Internet has also brought a huge market for the development of sensors. Industrial Internet and sensor development can be described as complementary.
This article was prepared by the Renke Technical Team. Renke is a professional manufacturer and solution provider specializing in environmental monitoring, industrial sensing, and IoT technologies. The content presented in this article is based on practical engineering experience, product development expertise, and real-world deployment cases.
